You've got some great watches on that short list.
And yeah, I would agree that amongst those, the Aquanaut would indeed be the most "under the radar" (if you can say that about any Patek) .
Argh... you are not helping me with that link! Nautilus vs Aquanaut?!?
Btw, you are correct in this being a first world problem. I think in the end, my wife would be much happier if I got the Aquanaut and increased our donations to some of the charities we support. We'll see....
I like Kaplan's suggestion of the discontinued IWC 3706. It has classic styling and is reasonably priced.
If I would also suggest Zenith's El Primero 1969. It doesn't have an outer bezel, but it does have a tachymeter on the dial. This is the 38mm version but there is also a 42 mm version which moves the date to the 6 . Good luck!
If your wife doesn't want you spending close to $20K on a watch, maybe you should nix the PP, AP, and VC from the possibilities for now. You know the old saying,"Happy wife, happy life." Maybe consider some more reasonably priced watches so you don't end up in the doghouse. You could consider offerings from JLC, IWC, Zenith and still have a very nice watch that flies under the radar, and also have a happy wife.